The present invention relates to a device for automatically sorting elements, such as caps, and feeding the elements to a discharge point in a specific orientation.
Apparatus for sorting articles from a mixed mass of articles on an inclined rotating surface and arranging the articles in single file for discharge, is available in the art. Apparatus of this sort, also referred to as orbital selecting or sorting devices, utilize centrifugal force to transfer the articles on the rotating surface to the perimeter of the surface for selecting or sorting. Some of the prior art devices utilize a plurality of recesses at the perimeter of the rotating surface to assist in the selection of the elements, such as the devices described in patents issued to Wysocki et al., U.S. Pat. No. 3,407,964, and Sterling, U.S. Pat. No. 3,696,924.
Apparatus such as those described in Greck, U.S. Pat. No. 3,747,738, Hausman et al., U.S. Pat. No. 2,888,169, and Ervine, U.S. Pat. No. 4,007,854, utilize orbital sorting techniques to transfer articles in a specific orientation to a discharge chute. In these prior art devices, no actual selection process is occurring, rather the articles are aligned automatically by operation of centrifugal force or gravity in the proper orientation for feeding. Since no selection is made on the basis of the orientation of the elements. the geometry of the elements that can be fed by these latter devices is limited. For instance, in the case of Irvine and Hausman et al., the elements are generally limited to a cylindrical shape.
In the patent to Mergl, U.S. Pat. No. 4,266,653, the elements rotating with the inclined surface are sorted while on the surface so that only elements in a specific orientation are fed through the discharge chute. In Mergl, the selection is performed by operation of gravity on stoppers situated in a perimetrical recess in the rotating surface. In the Mergl device, the selection process occurs at the highest point on the inclined surface, and is brought about by the operation of gravity on the center of gravity of the article to be selected. Thus, if the center of gravity is too high relative to the rotating surface, gravity will pull the piece out of the recess back into the hopper portions of the device. In this respect, the Mergl stoppering machine is limited to a small range of elements having a specific geometry and orientation of the center of gravity.
The apparatus described in Glaude, U.S. Pat. No. 2,388,405, allows selection based on the orientation of open ended hollow caps. In this apparatus, selection is performed by a stationary member that, in essence, pulls properly oriented caps off of the rotating surface and into the discharge chute. In this device, the selection process must occur at the lowest point on the incline device so that the parts or the elements may be fed off of the rotating surface.
None of the above-referenced patents utilizes a remote sensing means to sense the orientation of the part to be selected in order to activate some means to eject an improperly oriented part back into the body of the rotating surface. The devices of Wysocki et al. and Sterling use airjets to discharge improperly oriented caps, but the jets are continuously operating so that improperly oriented caps are automatically blown back into the rotating surface and out of the perimetrical recesses. The apparatus described in Greck utilizes a light source and photosensor, but only to stop the rotation of the inclined plate in the event that the discharge chute is full.
One problem with the orbital sorting devices of the prior art is the feeding speed of the devices has been limited to a maximum of about 1100 parts per minute. Devices that attempt to properly orient the elements to be sorted prior to entry into the discharge chute typically have the lowest feed rate. Apparatus such as in Wysocki and Glaude allow higher feed rates by discarding the improperly oriented parts and feeding only the properly oriented parts. There is a need for an orbital sorting device that produces a higher feed rate of properly oriented parts to the discharge chute.
It is, therefore, an object of the present invention to provide a device that is capable of much higher feed rates. It is a further object to provide an orbital sorting device that is as infallible as possible in feeding only properly oriented elements. Further objects and benefits of the present invention will be apparent from the ensuing description and accompanying figures.